Although advertisements on the web pages may degrade your experience, our business certainly depends on them and we can only keep providing you high-quality research based articles as long as we can display ads on our pages.

To view this article, you can disable your ad blocker and refresh this page or simply login.

Page 1 of 9 – SEC Filing

INFORMATION TO BE INCLUDED IN STATEMENTS
FILED PURSUANT TO RULES 13d-1 (b), (c) AND (d) AND AMENDMENTS THERETO FILED PURSUANT TO 13d-2 (b)

(Amendment No. ___________)*

Tocagen Inc.

(Name of
Issuer)

Common Stock

(Title of
Class of Securities)

888846102

(CUSIP Number)

April 13, 2017

(Date of
Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to
which this Schedule is filed:

¨Rule 13d-1(b)

x Rule
13d-1(c)

¨Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a
reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment
containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page
shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”)
or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however,
see the Notes).

(Continued on following pages)

Page 1 of 9

Exhibit Index on Page 8

Follow Tocagen IncFollow Tocagen Inc

Trade (TOCA) Now!

Page 2 of 9 – SEC Filing

1

NAME OF
REPORTING PERSONS Foresite Capital Fund III, L.P. (“FCF III”)

2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A
GROUP

(a) ¨ (b) x

3

SEC USE ONLY

4

CITIZENSHIP OR PLACE OF ORGANIZATIONDelaware

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH

5

SOLE VOTING POWER915,000 shares, except that Foresite Capital Management III, LLC (“FCM III”), the general partner of FCF III, may be deemed to have sole power to vote these shares, and James Tananbaum (“Tananbaum”), the managing member of FCM III, may be deemed to have sole power to vote these shares.

6

SHARED VOTING POWERSee response to row 5.

7

SOLE DISPOSITIVE POWER

915,000 shares, except that FCM III, the general partner of
FCF III, may be deemed to have sole power to dispose of these shares, and Tananbaum, the managing member of FCM III, may be deemed
to have sole power to dispose of these shares.

8

SHARED DISPOSITIVE POWERSee response to row 7.

9

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 915,000

10

CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

¨

11

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 4.6%*

12

TYPE OF REPORTING PERSON PN

* Percentage ownership as of April 21, 2017 is 4.63%, calculated
based on 19,776,763 shares outstanding, including the exercise of the Issuer’s underwriters’ option to purchase a
total of 1,275,000 additional shares of common stock from the Issuer, as announced by the Issuer on April 19, 2017.
This Schedule 13G is being filed because on April 13, 2017, FCF III owned an aggregate of 1,000,000 shares, representing 5.4% of
such class of shares. Prior to the filing of this Schedule 13G, the Issuer’s underwriters
purchased a total of 1,275,000 additional

shares of common stock from the Issuer, decreasing the aggregate ownership
of the Reporting Persons below 5%.

SOLE VOTING POWER915,000 shares, all of which are directly owned by Foresite Capital Fund III, L.P. (“FCF III”). FCM III, the general partner of FCF III, may be deemed to have sole power to vote these shares, and James Tananbaum (“Tananbaum”), the managing member of FCM III, may be deemed to have sole power to vote these shares.

6

SHARED VOTING POWERSee response to row 5.

7

SOLE DISPOSITIVE POWER915,000 shares, all of which are directly owned by FCF III. FCM III, the general partner of FCF III, may be deemed to have sole power to dispose of these shares, and Tananbaum, the managing member of FCM III, may be deemed to have sole power to dispose of these shares.

8

SHARED DISPOSITIVE POWERSee response to row 7.

9

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 915,000

10

CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

¨

11

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 4.6%*

12

TYPE OF REPORTING PERSON OO

* Percentage ownership as of April 21, 2017 is 4.63%, calculated
based on 19,776,763 shares outstanding, including the exercise of the Issuer’s underwriters’ option to purchase a
total of 1,275,000 additional shares of common stock from the Issuer, as announced by the Issuer on April 19, 2017.
This Schedule 13G is being filed because on April 13, 2017, FCF III owned an aggregate of 1,000,000 shares, representing 5.4% of
such class of shares, and FCM III may have been deemed to have sole power to vote and dispose of such shares. Prior to the filing
of this Schedule 13G, the Issuer’s underwriters purchased a total of 1,275,000 additional
shares of common stock from the Issuer, decreasing the aggregate ownership of the Reporting Persons below 5%.

Follow Tocagen IncFollow Tocagen Inc

Trade (TOCA) Now!

Page 4 of 9 – SEC Filing

1

NAME OF REPORTING PERSONS James Tananbaum (“Tananbaum”)

2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

(a) ¨ (b) x

3

SEC USE ONLY

4

CITIZENSHIP OR PLACE OF ORGANIZATIONUnited States

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH

5

SOLE VOTING POWER915,000 shares, all of which are directly owned by Foresite Capital Fund III, L.P. (“FCF III”). Tananbaum is the managing member of Foresite Capital Management III, LLC (“FCM III”), which is the general partner of FCF III. Tananbaum may be deemed to have sole power to vote these shares.

6

SHARED VOTING POWERSee response to row 5.

7

SOLE DISPOSITIVE POWER915,000 shares, all of which are directly owned by FCF III. Tananbaum is the managing member of FCM III, which is the general partner of FCF III. Tananbaum may be deemed to have sole power to dispose of these shares.

8

SHARED DISPOSITIVE POWERSee response to row 7.

9

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 915,000

10

CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

¨

11

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 4.6%*

12

TYPE OF REPORTING PERSON IN

* Percentage ownership as of April 21, 2017 is 4.63%, calculated
based on 19,776,763 shares outstanding, including the exercise of the Issuer’s underwriters’ option to purchase a
total of 1,275,000 additional shares of common stock from the Issuer, as announced by the Issuer on April 19, 2017.
This Schedule 13G is being filed because on April 13, 2017, FCF III owned an aggregate of 1,000,000 shares, representing 5.4% of
such class of shares, and Tananbaum may have been deemed to have sole power to vote and dispose of such shares. Prior to the filing
of this Schedule 13G, the Issuer’s underwriters purchased a total of 1,275,000 additional
shares of common stock from the Issuer, decreasing the aggregate ownership of the Reporting Persons below 5%.

Follow Tocagen IncFollow Tocagen Inc

Trade (TOCA) Now!

Page 5 of 9 – SEC Filing

ITEM 1(A).

NAME OF ISSUER

Tocagen Inc. (the “Issuer”)

ITEM 1(B).

ADDRESS OF ISSUER’S PRINCIPAL EXECUTIVE OFFICES

3030 Bunker Hill Street, Suite 230

San Diego, California 92109

ITEM 2(A).

NAME OF PERSONS FILING

This Schedule is filed by Foresite Capital Fund III, L.P., a Delaware limited partnership, Foresite Capital Management III, LLC, a Delaware limited liability company, and James Tananbaum. The foregoing entities and individuals are collectively referred to as the “Reporting Persons.”

ITEM 2(B).

ADDRESS OF PRINCIPAL OFFICE

The address for each of the Reporting Persons is:

c/o Foresite Capital Management

600 Montgomery Street, Suite 4500

San Francisco, CA 94111

ITEM 2(C).

CITIZENSHIP

See Row 4 of cover page for each Reporting Person.

ITEM 2(D).

TITLE OF CLASS OF SECURITIES

Common Stock

ITEM 2(D)

CUSIP NUMBER

888846102

ITEM 3.

If this statement is filed pursuant to Rule 13d-1(b), or 13d-2(b) or (c), check whether the person filing is a:

Not applicable.

Follow Tocagen IncFollow Tocagen Inc

Trade (TOCA) Now!

Page 6 of 9 – SEC Filing

ITEM 4.

OWNERSHIP

The following information with respect to the ownership of the common stock of the Issuer by the persons filing this Statement is provided as of April 21, 2017:

(a)

Amount beneficially owned:

See Row 9 of cover page for each Reporting Person.

(b)

Percent of Class:

See Row 11 of cover page for each Reporting Person.

(c)

Number of shares as to which such person has:

(i)

Sole power to vote or to direct the vote:

See Row 5 of cover page for each Reporting Person.

(ii)

Shared power to vote or to direct the vote:

See Row 6 of cover page for each
Reporting Person.

(iii)

Sole power to dispose or to direct the disposition of:

See Row 7 of cover page for each
Reporting Person.

(iv)

Shared power to dispose or to direct the disposition of:

See Row 8 of cover page for each Reporting Person.

ITEM 5.

OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS

If this statement is being filed to report the fact that as of the date hereof the Reporting Person has ceased to be the beneficial
owner of more than 5 percent of the class of securities, check the following x.

ITEM 6.

OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON.

Under certain circumstances set forth in the limited partnership agreement of FCF III and the limited liability company agreement
of FCM III the partners or members, as the case may be, of each of such entities may be deemed to have the right to receive dividends
from, or the proceeds from the sale of, shares of the Issuer directly or indirectly owned by each such entity of which they are
a partner or member.

ITEM 7.

IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING
COMPANY

Not applicable.

ITEM 8.

IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP.

Not applicable

ITEM 9.

NOTICE OF DISSOLUTION OF GROUP.

Not applicable

ITEM 10.

CERTIFICATION.

By signing below, I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and
are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were
not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than
activities solely in connection with a nomination under § 240.14a-11.

Follow Tocagen IncFollow Tocagen Inc

Trade (TOCA) Now!

Page 7 of 9 – SEC Filing

SIGNATURES

After reasonable inquiry and to the best of
my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Date: April 24, 2017

FORESITE CAPITAL FUND III, L.P.

By:

FORESITE CAPITAL MANAGEMENT III, LLC

Its:

General Partner

By:

/s/ James Tananbaum

Name:

James Tananbaum

Title:

Managing Member

FORESITE CAPITAL MANAGEMENT III, LLC

By:

/s/ James Tananbaum

Name:

James Tananbaum

Title:

Managing Member

JAMES TANANBAUM

By:

/s/ James Tananbaum

Name:

James Tananbaum

Follow Tocagen IncFollow Tocagen Inc

Trade (TOCA) Now!

Page 8 of 9 – SEC Filing

EXHIBIT INDEX

Found on Sequentially

Exhibit

Numbered Page

Exhibit A: Agreement of Joint Filing

9

Follow Tocagen IncFollow Tocagen Inc

Trade (TOCA) Now!

Page 9 of 9 – SEC Filing

exhibit A

Agreement of Joint Filing

The undersigned hereby
agree that a single Schedule 13G (or any amendment thereto) relating to the common stock of the Issuer shall be filed on behalf
of each of the undersigned and that this Agreement shall be filed as an exhibit to such Schedule 13G.